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1.
Eur J Med Chem ; 183: 111726, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31585275

RESUMO

Multidrug resistance (MDR) is a main cause of chemotherapy failure and patient death. This situation usually involves a glycoprotein (P-gp) mediated drug efflux, resulting in a low cellular drug concentration and insensitivity. Here we report the design, synthesis and evaluation of novel (+/-)-securinine bivalents as P-gp inhibitors in vitro and in vivo. MTT assays reflected that bivalent mimetics of securinine particularly the virosecurinine bivalent mimetic 8C showed promissing MDR reversal potential in both P-gp highly expressed cell line HepG2/DOX and MCF-7/ADM. At a 10 µM concentration, 8C can entirely reverse the resistance of HepG2/DOX to doxorubicin (DOX), and is more effective than the positive control verapamil (VRP). Fluorescence, flow cytometry, and DOX efflux assays demonstrated that 8C can facilitate the accumulation and diminish the efflux of intracellular DOX. Molecular docking analysis and western blot assays indicated that 8C accomplished this by competitively inhibiting the activity of P-gp rather than by affecting its expression. Compound 8C was also observed to reverse drug resistance effectively in xenograft models when combined with DOX. This study lays a foundation for the discovery of (+/-)-securinine ramifications as P-gp inhibitors and provides a promising lead compound 8C as a P-gp mediated MDR reversal agent.

2.
J Am Soc Nephrol ; 30(10): 2000-2016, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31537649

RESUMO

BACKGROUND: Although diabetic kidney disease demonstrates both familial clustering and single nucleotide polymorphism heritability, the specific genetic factors influencing risk remain largely unknown. METHODS: To identify genetic variants predisposing to diabetic kidney disease, we performed genome-wide association study (GWAS) analyses. Through collaboration with the Diabetes Nephropathy Collaborative Research Initiative, we assembled a large collection of type 1 diabetes cohorts with harmonized diabetic kidney disease phenotypes. We used a spectrum of ten diabetic kidney disease definitions based on albuminuria and renal function. RESULTS: Our GWAS meta-analysis included association results for up to 19,406 individuals of European descent with type 1 diabetes. We identified 16 genome-wide significant risk loci. The variant with the strongest association (rs55703767) is a common missense mutation in the collagen type IV alpha 3 chain (COL4A3) gene, which encodes a major structural component of the glomerular basement membrane (GBM). Mutations in COL4A3 are implicated in heritable nephropathies, including the progressive inherited nephropathy Alport syndrome. The rs55703767 minor allele (Asp326Tyr) is protective against several definitions of diabetic kidney disease, including albuminuria and ESKD, and demonstrated a significant association with GBM width; protective allele carriers had thinner GBM before any signs of kidney disease, and its effect was dependent on glycemia. Three other loci are in or near genes with known or suggestive involvement in this condition (BMP7) or renal biology (COLEC11 and DDR1). CONCLUSIONS: The 16 diabetic kidney disease-associated loci may provide novel insights into the pathogenesis of this condition and help identify potential biologic targets for prevention and treatment.

3.
Eur J Pharm Sci ; 140: 105058, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31472255

RESUMO

The biofilm formation of Pseudomonas aeruginosa (P. aeruginosa) is regulated by a phenomenon of quorum sensing (QS). With 5-hydroxyl-3,4-halogenated-5H-furan-2-ones as beginning, analogs bearing alkyl chains, vinyl bromide, or aromatic rings were designed and synthesized. The minimum inhibitory concentration (MIC) of the compounds against P. aeruginosa was assayed and the biofilm inhibition ratio was determined at different concentrations lower than the MIC. C-5 aromatic substituted furanones showed remarkable biofilm formation as well as inhibition of virulence factor production in P. aeruginosa. Fluorescence report analysis identified the QS regulatory mechanism of the most active compound 29. This study provides us a novel candidate for combating drug resistant bacteria strains by merely inhibiting biofilm formation. Without suppressing the regular life cycle of the bacteria, bacterial resistance mechanisms may not be activated.

4.
Leuk Res ; 85: 106198, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31401408

RESUMO

The aim of this study was to investigate the role and underlying mechanism of circular RNA (circRNA) circPAN3 in mediating drug resistance in acute myeloid leukemia (AML). We first established two doxorubicin (ADM)-resistant AML cell lines and then utilized high-throughput RNA sequencing (RNA-seq) to compare their circRNA expression profiles with those of the parental cell lines. With bioinformatic analysis, we identified key circRNA molecules involved in drug resistance and validated our findings in clinical specimens. The target microRNAs (miRNAs) and downstream mRNAs were also explored bioinformatically. Using RNA interference technique, the potential mechanism was further investigated. Twenty-nine circRNAs were identified to be differentially expressed between ADM-resistant and sensitive cells. We found that circPAN3 is most likely a key mediator in the development of AML drug resistance, evidenced by the increased expression in ADM-resistant cell lines and BM samples from relapsed patients. Additionally, downregulation of circPAN3 by small interfering RNA (siRNA) significantly restored drug sensitivity to ADM in the two ADM-resistant cell lines, but lentivirus-mediated circPAN3 overexpression had the opposite effect. Subsequent bioinformatic analysis and mechanistic experiments revealed that circPAN3 may facilitate AML drug resistance through regulating autophagy and influencing expression of apoptosis-related proteins, while AMPK/mTOR signaling plays a key role in the regulation of circPAN3 on autophagy. These findings may provide new important insights into the role of circRNAs in mediating AML drug resistance, and suggest that circPAN3 might be a potential target for treatment of drug-resistance AML, which merits further investigation and validation.

5.
Cancer Res ; 79(21): 5550-5562, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31431462

RESUMO

Neuroblastoma is the most common malignant disease of infancy, and amplification of the MYCN oncogene is closely associated with poor prognosis. Recently, expression of MYCN was shown to be inversely correlated with aryl hydrocarbon receptor (AHR) expression in neuroblastoma, and overexpression of AHR downregulated MYCN expression, promoting cell differentiation. Therefore, we further investigated the potential of AHR to serve as a prognostic indicator or a therapeutic target in neuroblastoma. First, the clinical significance of AHR in neuroblastoma was examined. Positive AHR immunostaining strongly correlated with differentiated histology of neuroblastoma and predicted better survival for patients. The mouse xenograft model showed that overexpression of AHR significantly suppressed neuroblastoma tumor growth. In addition, activation of AHR by the endogenous ligand kynurenine inhibited cell proliferation and promoted cell differentiation in vitro and in vivo. kynurenine treatment also upregulated the expression of KISS1, a tumor metastasis suppressor, and attenuated metastasis in the xenograft model. Finally, analysis of KISS1 levels in neuroblastoma patient tumors using the R2: Genomics Analysis and Visualization Platform revealed that KISS1 expression positively correlated with AHR, and high KISS1 expression predicted better survival for patients. In conclusion, our results indicate that AHR is a novel prognostic biomarker for neuroblastoma, and that overexpression or activation of AHR offers a new therapeutic possibility for patients with neuroblastoma. SIGNIFICANCE: These findings show that AHR may function as a tumor suppressor in childhood neuroblastoma, potentially influencing the aetiologic and therapeutic targeting of the disease.

6.
Drug Dev Res ; 80(6): 750-757, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31169945

RESUMO

The prevalence of multidrug resistance among clinically significant bacterial pathogens underlines a critical need for the development of new classes of antibacterial agents with novel structural scaffolds. Cajaninstilbene acid (CSA), which is isolated from pigeonpea leaves, has shown potent antibacterial activity. In this study, a series of 2-hydroxyl-4-methoxyl-3-(3-methylbut-2-en-1-yl)-6-(4-phenylbenzoylamino)benzoic acid derivatives derived from CSA were designed and synthesized, and their antibacterial activities were evaluated. Several synthesized compounds exhibit better antibacterial activity than CSA against Staphylococcus aureus, Staphylococcus epidermidis, and two strains of methicillin-resistant S. aureus. Meanwhile, the results of 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide assays illustrate the good selectivity between bacteria and normal cells of the most active compounds 6u and 6v. Furthermore, well combinations with bacterial RNA polymerase of 6u arising from docking study imply the possible mechanism of antibacterial activity of these synthetic compounds.

7.
Curr Med Sci ; 39(3): 403-409, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31209810

RESUMO

Accumulation of lactate in tumor has been linked to poor prognosis of oral squamous cell carcinoma (OSCC), but the underlying mechanism remained largely uncertain. Previous studies have suggested that presence of cancer stem cells (CSCs) closely correlated with cellular malignancy of OSCC. Here, using 3D organoid culture model, we investigated whether lactate promoted CSCs phenotype in primary OSCC cells. We generated organoids using fresh OSCC specimens and verified that organoids recapitulated histopathology and cellular heterogeneity of parental tumor. Organoids were then transfected with a Wnt reporter to visualize Wnt activity. The sphere forming assay demonstrated that high Wnt activity functionally designated CSCs population in OSCC cells. Further investigations indicated that lactate treatment promoted Wnt activity and increased the expression of CSCs (i.e. CD133+ cells) in organoids. Moreover, silencing monocarboxylate transporter 1 (MCT1), the prominent path for lactate uptake in human tumor with siRNA significantly impaired organoid forming capacity of OSCC cells. Together, our study demonstrated that lactate can promote CSCs phenotype of OSCC, and MCT1 may be a therapeutic target against OSCC growth.

9.
Cancer Med ; 8(8): 4032-4042, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31112373

RESUMO

BACKGROUND: The goal of this study was to establish and validate two nomograms for predicting the long-term overall survival (OS) and cancer-specific survival (CSS) in lip squamous cell carcinoma (LSCC). METHODS: This study selected 4175 patients who were diagnosed with LSCC between 2004 and 2015 in the SEER (Surveillance, Epidemiology, and End Results) database. The patients were allocated randomly to a training cohort and validation cohort. Variables were selected using a backward stepwise method in a Cox regression model. Based on the predictive model with the identified prognostic factors, nomograms were established to predict the 3-, 5-, and 8-year survival OS and CSS rates of LSCC patients. The accuracy of the nomograms was evaluated based on the consistency index (C-index), while their prediction accuracy was evaluated using calibration plots. Decision curve analyses (DCAs) were used to evaluate the performance of our survival model. RESULTS: The multivariate analyses demonstrated that age at diagnosis, marital status, sex, race, American Joint Committee on Cancer stage, surgery status, and radiotherapy status were risk factors for both OS and CSS. The C-index, area under the time-dependent receiver operating characteristic curve, and calibration plots demonstrated the good performance of the nomograms. DCAs of both nomograms further showed that they exhibited good 3-, 5-, and 8-year net benefits. CONCLUSIONS: We have developed and validated LSCC prognosis nomograms for OS and CSS for the first time. These nomograms can be valuable tools for clinical practice when clinicians are helping patients to understand their survival risk for the next 3, 5, and 8 years.

10.
Clin Cancer Res ; 25(14): 4542-4551, 2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-31000589

RESUMO

PURPOSE: Renal cell carcinoma (RCC) is known to be highly radioresistant but the mechanisms associated with radioresistance have remained elusive. We found DOC-2/DAB2 interactive protein (DAB2IP) frequently downregulated in RCC, is associated with radioresistance. In this study, we investigated the underlying mechanism regulating radioresistance by DAB2IP and developed appropriate treatment. EXPERIMENTAL DESIGN: Several RCC lines with or without DAB2IP expression were irradiated with ionizing radiation (IR) for determining their radiosensitivities based on colony formation assay. To investigate the underlying regulatory mechanism of DAB2IP, immunoprecipitation-mass spectrometry was performed to identify DAB2IP-interactive proteins. PARP-1 expression and enzymatic activity were determined using qRT-PCR, Western blot analysis, and ELISA. In vivo ubiquitination assay was used to test PARP-1 degradation. Furthermore, in vivo mice xenograft model and patient-derived xenograft (PDX) model were used to determine the effect of combination therapy to sensitizing tumors to IR. RESULTS: We notice that DAB2IP-deficient RCC cells acquire IR-resistance. Mechanistically, DAB2IP can form a complex with PARP-1 and E3 ligases that is responsible for degrading PARP-1. Indeed, elevated PARP-1 levels are associated with the IR resistance in RCC cells. Furthermore, PARP-1 inhibitor can enhance the IR response of either RCC xenograft model or PDX model. CONCLUSIONS: In this study, we unveil that loss of DAB2IP resulted in elevated PARP-1 protein is associated with IR-resistance in RCC. These results provide a new targeting strategy to improve the efficacy of radiotherapy of RCC.

11.
Int J Mol Sci ; 20(7)2019 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-30987025

RESUMO

BACKGROUND: S1P has been shown to improve the endothelialization of decellularized vascular grafts in vitro. Here, we evaluated the potential of tissue-engineered vascular grafts (TEVGs) constructed by ECs and S1P on decellularized vascular scaffolds in a rat model. METHODS: Rat aorta was decellularized mainly by 0.1% SDS and characterized by histology. Rat ECs, were seeded onto decellularized scaffolds, and the viability of the ECs was evaluated by biochemical assays. Then, we investigated the in vivo patency rate and endothelialization for five groups of decellularized vascular grafts (each n = 6) in a rat abdominal aorta model for 14 days. The five groups included (1) rat allogenic aorta (RAA); (2) decellularized RAA (DRAA); (3) DRAA with S1P (DRAA/S1P); (4) DRAA with EC recellularization (DRAA/EC); and (5) DRAA with S1P and EC recellularization (DRAA/EC/S1P). RESULTS: In vitro, ECs were identified by the uptake of Dil-Ac-LDL. S1P enhanced the expression of syndecan-1 on ECs and supported the proliferation of ECs on decellularized vascular grafts. In vivo, RAA and DRAA/EC/S1P both had 100% patency without thrombus formation within 14 days. Better endothelialization, more wall structure maintenance and less inflammation were noted in the DRAA/EC/S1P group. In contrast, there was thrombus formation in the DRAA, DRAA/S1P and DRAA/EC groups. CONCLUSION: S1P could inhibit thrombus formation to improve the patency rate of EC-covered decellularized vascular grafts in vivo and may play an important role in the construction of TEVGs.


Assuntos
Prótese Vascular , Células Endoteliais/metabolismo , Lisofosfolipídeos/metabolismo , Esfingosina/análogos & derivados , Grau de Desobstrução Vascular , Animais , Aorta/transplante , Implante de Prótese Vascular , Proliferação de Células , Forma Celular , Feminino , Macrófagos/metabolismo , Ratos Sprague-Dawley , Esfingosina/metabolismo , Análise de Sobrevida , Sindecana-1/metabolismo
12.
Diabetes Care ; 42(3): 406-415, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30659077

RESUMO

OBJECTIVE: Genetic risk scores (GRS) have been developed that differentiate individuals with type 1 diabetes from those with other forms of diabetes and are starting to be used for population screening; however, most studies were conducted in European-ancestry populations. This study identifies novel genetic variants associated with type 1 diabetes risk in African-ancestry participants and develops an African-specific GRS. RESEARCH DESIGN AND METHODS: We generated single nucleotide polymorphism (SNP) data with the ImmunoChip on 1,021 African-ancestry participants with type 1 diabetes and 2,928 control participants. HLA class I and class II alleles were imputed using SNP2HLA. Logistic regression models were used to identify genome-wide significant (P < 5.0 × 10-8) SNPs associated with type 1 diabetes in the African-ancestry samples and validate SNPs associated with risk in known European-ancestry loci (P < 2.79 × 10-5). RESULTS: African-specific (HLA-DQA1*03:01-HLA-DQB1*02:01) and known European-ancestry HLA haplotypes (HLA-DRB1*03:01-HLA-DQA1*05:01-HLA-DQB1*02:01, HLA-DRB1*04:01-HLA-DQA1*03:01-HLA-DQB1*03:02) were significantly associated with type 1 diabetes risk. Among European-ancestry defined non-HLA risk loci, six risk loci were significantly associated with type 1 diabetes in subjects of African ancestry. An African-specific GRS provided strong prediction of type 1 diabetes risk (area under the curve 0.871), performing significantly better than a European-based GRS and two polygenic risk scores in independent discovery and validation cohorts. CONCLUSIONS: Genetic risk of type 1 diabetes includes ancestry-specific, disease-associated variants. The GRS developed here provides improved prediction of type 1 diabetes in African-ancestry subjects and a means to identify groups of individuals who would benefit from immune monitoring for early detection of islet autoimmunity.


Assuntos
Grupo com Ancestrais do Continente Africano/genética , Diabetes Mellitus Tipo 1/etnologia , Diabetes Mellitus Tipo 1/genética , Testes Genéticos , Antígenos HLA-D/genética , Grupo com Ancestrais do Continente Africano/estatística & dados numéricos , Alelos , Estudos de Casos e Controles , Grupo com Ancestrais do Continente Europeu/genética , Feminino , Predisposição Genética para Doença , Testes Genéticos/métodos , Testes Genéticos/normas , Estudo de Associação Genômica Ampla , Cadeias alfa de HLA-DQ/genética , Cadeias beta de HLA-DQ/genética , Cadeias HLA-DRB1/genética , Haplótipos , Humanos , Masculino , Polimorfismo de Nucleotídeo Único , Valor Preditivo dos Testes , Projetos de Pesquisa , Fatores de Risco
13.
Bioorg Med Chem Lett ; 29(5): 749-754, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30630718

RESUMO

Signal molecules are stimulators of multiple quroum-sensing virulence and biofilm formation. Small molecule analogues have been suspected as a potent inhibitor in therapeutic strategy. Herein, we synthesized a series of small molecule compounds from the 2, 8-bit derivatives of quinoline by Suzuki coupling reaction. We found that these compounds have the biofilm inhibitory effect in normal condition instead of phosphate limitation state. Furthermore, lacZ reporter strain assay and rhamnolipids as well as pyocyanin experiments showed that these compounds did not affect las and pqs system but reduced the expression of rhl. All these results suggest that quinoline derivatives can be treated as potent inhibitors against biofilm and reduce virulence through the rhl system. This research will be useful in designing new quorum sensing inhibitors to attenuate the infection of bacteria.

14.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 26(6): 1688-1694, 2018 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-30501705

RESUMO

OBJECTIVE: To investigate relationship of miRNA-132, miRNA-256, miRNA-143 and miRNA-145 level with antophagy and apoptosis of multiple mgeloma cells. METHODS: Human myeloma cell line U266 and normal CD138+ plasma cells were selected and used for study and detection, the 45 cases of MM were enrolled in MM group, and 40 normal persons were sellectod in control group. The expression of miRNA-132, miRNA-125b, miRNA-143 and miRNA-145 were measured by using qPCR, the expressions of autophagy-related protein (LC3-Ⅱ, LC3-Ⅰ, P62, beclin-1) and apoptosis-related molecules (cleaved-Caspase3, cleaved-Caspase7, BCL-2, BAX) were measured by using Western blot, respectively. The rate of apoptosis was measured by using flow cytometry. The correlation of miRNA expression level with clinical-related indexes including M protein, hemoglobin, ß2-MG, lactate dehydrogenase, albumin, creatinine and serum calcium was analyzed. RESULTS: Compared with normal plasma cells, the expression of miRNA-132 and miRNA-125b in myeloma cells increased significantly (P<0.05), and the expression of miRNA-143 and miRNA-145 decreased significantly (P<0.05), but the expression of LC3-Ⅱ/LC3-Ⅰ and Beclin-1 increased significantly (P<0.05). The expression of P62. BAX, cleaved-Caspase3 and cleaved-Caspase7 decreased significantly (P<0.05), the BCL-2 expression increased significantly (P<0.05), but the rate of apoptosis decreased (P<0.05). After transfection with miRNA-125b mimic or miRNA-143 inhibitor by using the cationic liposomes, the LC3-Ⅱ /LC3-Ⅰ of normal plasma cells increased significantly (P<0.05), the expression of Beclin-1 significantly increased (P<0.05), the expression of P62 decreased significantly (P<0.05), and the apoptosis rate decreased (P<0.05). However, the apoptosis rate was not significantly changed after addition of the autophagic inhibitor 3-MA in the reaction system(P>0.05). The expressions of miRNA-132, miRNA-125b, miRNA-143 and miRNA-145 were significantly different between DS and ISS staging group, also between the patients with abnormal and normal chromosome karyotype (P<0.05). The miRNA-125b and miRNA-143 significantly correlated with the levels of ß2-MG, albumin and hemoglobin (P<0.05). CONCLUSION: The expressions of miRNA-132, miRNA-125b, miRNA-143 and miRNA-145 in patients with multiple myeloma closely relate with the clinical characteristics. Both over-expression of miRNA-125b and down-expression of miRNA-143 inhibit the apoptosis of myeloma cells by up-regulation of autophagy.

15.
Genome Med ; 10(1): 97, 2018 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-30572963

RESUMO

BACKGROUND: In recent years, research has consistently proven the occurrence of genetic overlap across autoimmune diseases, which supports the existence of common pathogenic mechanisms in autoimmunity. The objective of this study was to further investigate this shared genetic component. METHODS: For this purpose, we performed a cross-disease meta-analysis of Immunochip data from 37,159 patients diagnosed with a seropositive autoimmune disease (11,489 celiac disease (CeD), 15,523 rheumatoid arthritis (RA), 3477 systemic sclerosis (SSc), and 6670 type 1 diabetes (T1D)) and 22,308 healthy controls of European origin using the R package ASSET. RESULTS: We identified 38 risk variants shared by at least two of the conditions analyzed, five of which represent new pleiotropic loci in autoimmunity. We also identified six novel genome-wide associations for the diseases studied. Cell-specific functional annotations and biological pathway enrichment analyses suggested that pleiotropic variants may act by deregulating gene expression in different subsets of T cells, especially Th17 and regulatory T cells. Finally, drug repositioning analysis evidenced several drugs that could represent promising candidates for CeD, RA, SSc, and T1D treatment. CONCLUSIONS: In this study, we have been able to advance in the knowledge of the genetic overlap existing in autoimmunity, thus shedding light on common molecular mechanisms of disease and suggesting novel drug targets that could be explored for the treatment of the autoimmune diseases studied.


Assuntos
Doenças Autoimunes/genética , Predisposição Genética para Doença , Polimorfismo de Nucleotídeo Único , Artrite Reumatoide/genética , Doença Celíaca/genética , Diabetes Mellitus Tipo 1/genética , Estudo de Associação Genômica Ampla , Humanos , Anotação de Sequência Molecular , Escleroderma Sistêmico/genética
16.
Am J Hum Genet ; 103(5): 691-706, 2018 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-30388399

RESUMO

C-reactive protein (CRP) is a sensitive biomarker of chronic low-grade inflammation and is associated with multiple complex diseases. The genetic determinants of chronic inflammation remain largely unknown, and the causal role of CRP in several clinical outcomes is debated. We performed two genome-wide association studies (GWASs), on HapMap and 1000 Genomes imputed data, of circulating amounts of CRP by using data from 88 studies comprising 204,402 European individuals. Additionally, we performed in silico functional analyses and Mendelian randomization analyses with several clinical outcomes. The GWAS meta-analyses of CRP revealed 58 distinct genetic loci (p < 5 × 10-8). After adjustment for body mass index in the regression analysis, the associations at all except three loci remained. The lead variants at the distinct loci explained up to 7.0% of the variance in circulating amounts of CRP. We identified 66 gene sets that were organized in two substantially correlated clusters, one mainly composed of immune pathways and the other characterized by metabolic pathways in the liver. Mendelian randomization analyses revealed a causal protective effect of CRP on schizophrenia and a risk-increasing effect on bipolar disorder. Our findings provide further insights into the biology of inflammation and could lead to interventions for treating inflammation and its clinical consequences.

17.
Exp Hematol ; 2018 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-30395908

RESUMO

The contribution and role of circular RNAs (circRNAs) in mediating chemoresistance in acute myeloid leukemia (AML) are still poorly understood and need further investigation. In this study, we established a doxorubicin (ADM)-resistant THP-1 AML cell line (THP-1/ADM). A high-throughput microarray was used to identify circRNA expression profiles of THP-1/ADM cells and naive THP-1 cells. The identified potential functional circRNA molecule was further validated in THP-1/ADM cells and bone marrow (BM) specimens from 42 AML patients. The interactions with target microRNAs (miRNAs) and downstream messenger RNAs (mRNAs) were also explored. As a result, 49 circRNAs that are significantly differentially expressed between THP-1/ADM and THP-1 cells were identified. Of these circRNAs, downregulation of circPAN3 by small interfering RNA significantly restored ADM sensitivity of THP-1/ADM cells. Furthermore, BM samples from patients with refractory and recurrent AML showed increased expression of circPAN3. A detailed circRNA/miRNA/mRNA interaction network was predicated for this circRNA. Subsequent mechanistic experiments showed that downregulation of circPAN3 could decrease the expression of X-linked inhibitor of apoptosis protein (XIAP), but this effect was counteracted by miR-153-3p or miR-183-5p specific inhibitors. Luciferase experiments further demonstrated that these molecules are involved in the circPAN3 regulatory network. Our results revealed that circPAN3 may be a key mediator for chemoresistance of AML cells, which may depend on the circPAN3-miR-153-5p/miR-183-5p-XIAP axis. Our findings provide evidence that circPAN3 can be a valuable indicator for predicting clinical efficacy of chemotherapy in AML patients and also can serve as a potential target for reversing drug resistance in AML.

18.
Cancers (Basel) ; 10(11)2018 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-30384405

RESUMO

Prostate cancer (PCa) is the most common noncutaneous cancer in men worldwide. One of its major treatments is androgen deprivation therapy, but PCa frequently relapses as aggressive castration resistant local tumors and distal metastases. Hence, the development of novel agents or treatment modalities for advanced PCa is crucial. Many tumors, including PCa, first metastasize to regional lymph nodes via lymphatic vessels. Recent findings demonstrate that the bioactive lipid lysophosphatidic acid (LPA) promotes PCa progression by regulating vascular endothelial growth factor-C (VEGF-C), a critical mediator of tumor lymphangiogenesis and lymphatic metastasis. Many of the underlying molecular mechanisms of the LPA⁻VEGF-C axis have been described, revealing potential biomarkers and therapeutic targets that may aid in the diagnosis and treatment of advanced PCa. Herein, we review the literature that illustrates a functional role for LPA signaling in PCa progression. These discoveries may be especially applicable to anti-lymphangiogenic strategies for the prevention and therapy of metastatic PCa.

19.
J Nat Prod ; 2018 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-30444360

RESUMO

The quorum sensing (QS) system inhibitors of Pseudomonas aeruginosa are thought to attenuate bacterial pathogenicity and drug resistance by inhibiting biofilm formation and the production of virulence factors. In this study, a synthetic approach to the natural products cajaninstilbene acid (1) and amorfrutins A (2) and B (3) has been developed and was characterized by the Heck reaction, which was used to obtain the stilbene core and a Pinick oxidation to give the O-hydroxybenzoic acid. The biological activities of these compounds against the P. aeruginosa quorum sensing systems were evaluated. Amorfrutin B (3) showed promising antibiofilm activity against P. aeruginosa PAO1 with a biofilm inhibition ratio of 50.3 ± 2.7. Three lacZ reporter strains were constructed to identify the effects of compound 3 on different QS systems. Suppression efficacy of compound 3 on the expression of lasB-lacZ and pqsA-lacZ as well as on the production of their corresponding virulence factors elastase and pyocyanin was observed.

20.
Cell Physiol Biochem ; 50(2): 597-611, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30317243

RESUMO

BACKGROUND/AIMS: Hyperglycemia has been shown to increase the incidence and metastasis in various types of cancers. However, the correlation between hyperglycemia and lymphatic metastasis in prostate cancer (PCa) remains unclear. Our previous study demonstrated that lysophosphatidic acid (LPA) enhances vascular endothelial growth factor-C (VEGF-C) expression, a lymphangiogenic factor, through activating it receptors LPA1/3 in prostate cancer (PCa) cells. Moreover, hyperglycemia up-regulates autotaxin (ATX) expression, a LPA-generating enzyme. Therefore, we propose that high glucose promotes VEGF-C expression through LPA signaling in PCa cells. METHODS: Pharmacological inhibitors and siRNAs were utilized to investigate the molecular mechanism of high glucose-induced VEGF-C expression. Real-time PCR and Western blot were used to determine the mRNA and protein expressions, respectively. Cellular bioenergetics analysis was performed to determine the glycolysis levels. RESULTS: We demonstrated that the expressions of VEGF-C, ATX, and calreticulin were increased upon high glucose treatments in PC-3 cells. Moreover, high glucose-induced VEGF-C expression was mediated through the LPA1/3, PLC, Akt, ROS and LEDGF-dependent pathways. Additionally, high glucose enhanced the aerobic glycolysis via LPA1/3. CONCLUSION: These results indicated that hyperglycemia leads to LPA synthesis, and subsequent promoting pathological consequence of PCa. These novel findings could potentially provide new strategies for PCa treatments.


Assuntos
Glucose/farmacologia , Transdução de Sinais/efeitos dos fármacos , Fator C de Crescimento do Endotélio Vascular/metabolismo , Calreticulina/antagonistas & inibidores , Calreticulina/genética , Calreticulina/metabolismo , Linhagem Celular Tumoral , Glicólise , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/genética , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Lisofosfolipídeos/metabolismo , Masculino , Consumo de Oxigênio/efeitos dos fármacos , Fosfoinositídeo Fosfolipase C/genética , Fosfoinositídeo Fosfolipase C/metabolismo , Diester Fosfórico Hidrolases/genética , Diester Fosfórico Hidrolases/metabolismo , Neoplasias da Próstata/patologia , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Receptores de Ácidos Lisofosfatídicos/antagonistas & inibidores , Receptores de Ácidos Lisofosfatídicos/genética , Receptores de Ácidos Lisofosfatídicos/metabolismo , Regulação para Cima/efeitos dos fármacos , Fator C de Crescimento do Endotélio Vascular/genética
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